Wire containment apparatus for wire drawing machines

ABSTRACT

A wire drawing machine is provided with a pressure roller in the form of a roller sized to extend substantially across the width of the capstan and engage multiple turns of wire thereon in a lower quadrant on the exit side of the capstan. The pressure roller is mounted for pivoting about a horizontal axis parallel to the axis of the capstan, and for automatic angular positioning and alignment as contact is made with the wraps of wire on the capstan.

CROSS REFERENCES TO RELATED APPLICATIONS

[0001] This application claims priority to U.S. Provisional PatentApplication S/N 60/193,996, filed April 1, 2000.

BACKGROUND OF THE INVENTION

[0002] 1. Field of Invention

[0003] The present invention relates to wire containment apparatussuitable for use on conventional in-line wire drawing machines.

[0004] 2. Description of Prior Art

[0005] Prior wire containment apparatus for in-line wire drawingmachines utilizing a non-tapered capstan include a final contactpressure roller that is adapted for engaging the last wrap of wire onthe capstan in order to clamp the wire in position on the capstan anddevelop traction between the capstan and the wire to draw the wirethrough the die. However, there are several drawbacks and disadvantagesassociated with such prior final contact wire containment rollers.

[0006] Such rollers must apply a substantial pressure onto the last wrapto firmly hold the wire on the capstan and develop the necessarytraction therebetween for pulling the wire through the draw die.Consequently, these rollers must be changed when running wire ofsubstantially different sizes in order to precisely match the rollersize with the wire size, and to develop and maintain the desired wireposition and pressure. This results in substantial expense for changingand setup time for each different size wire run on the machine. In aneffort to minimize this setup time, and to provide for operator safety,these final contact rollers are positioned in an upper quadrant of thecapstan to provide ease of operator viewing and alignment with the lastwire wrap on the capstan. Consequently, the wire tends to sag or dropsubstantially as it exits from the lower quadrant of the capstan. Thisresults in an associated wire length and weight that the speedcompensating arm must accommodate in controlling the operation of thecapstan.

Summary of the Invention

[0007] The general aim of the present invention is to provide a new andimproved wire containment apparatus for in-line wire draw machinesutilizing non-tapered capstans which eliminates the aforementioneddrawbacks and disadvantages or prior wire containment final contactrollers.

[0008] An objective of the invention is to provide apparatus whichreduces the pressure needed to develop the necessary traction betweenthe wire and the capstan in order to assist in avoiding flattening ordeformation of the drawn wire, and which reduces the operating pressuresin the apparatus therefor.

[0009] Another objective of the invention is to reduce the need forchanging the final contact rollers of prior machines for different wiresizes, thereby reducing the expense of the machine and setup time whenchanging from running different wire sizes.

[0010] A more detailed objective is to achieve the foregoing byproviding final contact wire containment apparatus that isself-adjusting and adapted for use with wire of different sizes.

[0011] Yet another objective is to provide wire containment apparatuswhich reduces the sagging of wire as it exits the capstan, to reduce thelength and weight of the wire reflected to the speed compensating arm.This enables the compensating arm to operate at lower pressures, andwith increased sensitivity.

[0012] These and other objectives and advantages of the invention willbecome more apparent from the following detailed description when takenin conjunction with the accompanying drawings.

Brief Description of the Drawings

[0013]FIG. 1A is a front view of one-type of in-line wire draw machineshowing a conventional prior art final contact wire containmentapparatus.

[0014]FIG. 1B. is a front view of the wire draw machine of FIG. 1A butshowing a unique wire containment apparatus according to the presentinvention.

[0015]FIG. 2 is a top view of the machine of FIG. 1B taken along theline 2-2 of FIG. 1B with portions of the housing shown removed.

[0016]FIG. 3 is a right side view of the wire draw machine of FIG. 1Btaken along the line 3-3 of FIG. 2.

[0017]FIG. 4A is a rear view of the back wall of the capstan housing andcertain components thereof including components of the prior art wirecontainment apparatus of FIG. 1A

[0018]FIG. 4B is a rear view of the back wall of the capstan housing andcertain components thereof including components of the improved wirecontainment apparatus of the present invention of the embodiment of FIG.1A as seen substantially along the line 4-4 of FIG. 3.

[0019]FIGS. 5A and 5B are top and side views, respectively, of thecapstan and certain other components, including the wire containmentapparatus of the prior art configuration of FIG. 1A and the presentinvention embodiment of FIG. 1B.

[0020]FIG. 6 is an enlarged perspective view of the wire containmentapparatus embodiment of the present invention shown separate from thewire draw machine for purpose of clarity of understanding.

[0021]FIGS. 7, 8 and 9 are rear, right side and top plan views,respectively, of the separate wire containment apparatus shown in FIG.6.

[0022]FIG. 10 is a cross-sectional view taken along the line 10-10 ofFIG. 9.

[0023] While the invention is susceptible of various modifications andalternative constructions, a certain illustrated embodiment has beenshown in the drawings and will be described below in detail. It shouldbe understood, however, that there is no intention to limit theinvention to the specific forms disclosed, but on the contrary, theintention is to cover all modifications, alternative constructions, andequivalents falling within the spirit and scope of the invention.

DETAILED DESCRIPTION OF THE INVENTION

[0024] For purposes of illustration, the present invention is shown inthe drawings as wire containment apparatus 200 (see FIGS. 6-9) inconnection with a wire drawing machine 10B (FIG. 1B) equipped with anintegral turntable. As will be apparent, the wire containment apparatusof the present invention is equally suitable for use an other types ofwire draw machines.

[0025] Also shown in the drawings is an inline wire drawing machine 10A(FIG. 1A) which is substantially similar to machine 10B except asdescribed further below in connection with the wire containmentapparatus of the present invention; the machine 10A being provided witha conventional prior art wire containment apparatus for purposes ofcomparison and contrasting with the present invention; with the samenumeral identifiers being used for the same parts, components,assemblies, etc. for the machines 10A and 10B.

[0026] The basic structure, function and operation of the wire drawmachine 10A, and therefore machine 10B with the exception of the wirecontainment apparatus, has been fully explained and described in U.S.Pat. No. 6,125,675; a the copy of which is attached hereto andincorporated herein and made a part hereof herein by reference.

[0027] Briefly, electric motor 22 (FIG. 2) power rotates capstan 20 withwire 11C wrapped therearound to draw the wire from the coil of wire 11and through the draw die 12. From the capstan, the wire is pulled arounda speed compensating roller/arm assembly 36, and is drawn into a wireusing machine or station (not shown) via power rotated rollers 38.

[0028] In accordance with the present invention, the wire containmentapparatus 200 includes a roller assembly 210 (FIG. 1B) adapted forautomatic position adjustment and self-alignment of a roller 222 againstthe wire 11C wrapped around the capstan 20. As a result, and as furtherdescribed below, the wire containment apparatus 200 of the presentinvention is less expensive than conventional prior wire containmentapparatus, is more easily positioned by the machine operator, andresults in a wire draw machine that can operate at greater efficiencyand with improved capacity.

[0029] Briefly, the wire containment apparatus 200 comprises an actuator220 that is operatively connected to the roller assembly 210 forswinging the roller 222 about an axis “AA” (FIG. 1B) that is parallel tothe rotational axis of the capstan, and into and out of engagement withthe wire 11C on the capstan 20. The roller is mounted in the rollerassembly for pivoting about orthogonal axes “BB” and “CC” to effectautomatic angular position adjustment and selfalignment into pressureengagement with the wire wrapped on the capstan as the roller swingsupwardly (as viewed in FIG. 1B) toward the capstan. Thus, the freedom ofmovement of the roller assembly automatically compensates for taperingof the capstan resulting from wear, and for dimensional and angulardeviations in size and positioning of the capstan and the wirecontainment apparatus resulting from normal manufacturing tolerances.

[0030] In carrying out the invention, the actuator 220 is mounted to astationary frame or structural member of the machine 10B, and isoperatively connected to the roller assembly 210 through a linkageassembly 230. The actuator assembly shown comprises a conventional-typeactuator having an actuator housing connected to extension member 224 ofthe back wall 18 of the capstan housing via threaded fasteners 226, aninternal piston (not shown) operative for linear movement between twostroke ends in response to regulated actuating pressure supplied throughhose 228 from, and a piston rod 232 connected thereto for linearmovement as indicated by arrow EE (FIG. 7) between the two stroke endswith the actuator piston. In the present instance, the actuator is asingle-acting pneumatic actuator which is spring biased in onedirection, such as for disengagement between the roller and the wire onthe capstan, and is provided with a conventional elastomer diaphragm(not shown) connected to the piston, the diaphragm and piston beingpressure responsive in the other direction to overcome the spring biasand stroke the piston.

[0031] The linkage assembly 230 includes a torque transfer stepped shaft234 extending through back wall 18 and tube 235 and rotary supportingbushing 236 or bearing fixed therein, and a lever 238 connected to therear end of the shaft via fastener 240 extending through alignedopenings in bearing washer 242 and the lever and threaded longitudinallyinto the end of the shaft. The lever extends radially from the shaft andis pivotally connected to clevis 244 mounted to the free end of thepiston rod with a pivot pin 246 for establishing a pivoting connectiontherebetween. With this arrangement, the lever swings about axis AA asindicated by arrow FF in FIG. 7, as the piston and piston rod strokelinearly along EE in the actuator, in turn causing the shaft 234 to turnthrough an angular rotation within the limits established by thegeometric parameters of the piston stroke length and radial distancebetween pivot pin 246 and axis AA.

[0032] The forward end of the torque transfer shaft 234 is connected toa support block 250 of the roller assembly 210 for pivoting of thesupport block about axis “AA” with the shaft. In the embodiment shown,the shaft extends substantially through the support block and is securedtherein with fastener 240 extending through bearing washer 242 andthreaded longitudinally into the forward end of the shaft. In thisinstance, the shaft and support block are further secured for torquetransfer purposes via key 252 located in keyway 254 extending radiallyand longitudinally into the shaft and support block.

[0033] The roller 222 is mounted in bearings 258 located in support arms260 for freely rotating about rotational axis DD extendinglongitudinally therethrough. To effect 2-degree of freedom of rollerangular positioning on orthogonal axes, the arms 260 are connected witha center brace 262 that is in turn pivotally connected to a center block264 via pivot pin 266. The center block is in turn pivotally connectedto the support block via pivot pin 268 in an arrangement commonly knownas a pivoting knuckle. These pivot pin installation arrangements maytake any of a number of suitable embodiments, such as shown in FIG.wherein pin 268 is pressed into an interference-fit opening 270 in thesupport block, with the pin pivotally extending through an optionalbushing 272 pressed into the center block and a retaining ring 274 orother suitable arrangement maintaining the center block in position onthe pin. Similarly, the pin 266 is held in position with retaining rings281 for a free-floating pivot pin connection, or alternately may bepressed though interference-fit openings 276 extending through thecenter block and through an optional bushing 278 in the brace. In anyevent, the particular pivot pin arrangement utilized permits such twodegree of angular freedom of movement.

[0034] In preferred embodiments, limitations are established for thetwo-degree of freedom angular movement of the roller. In the embodimentshown, the dimensional clearance between the floor and the capstan limitfree rotation about the CC axis. Alternately, positive angular stops areestablished between the support and center blocks. Limitation ofrotation about the BB axis is established by a pair of threadedfasteners 291 and associated jam nuts, located on each side of thecenter block, and threaded through ears welded thereto.

[0035] With this arrangement, the roller freely rolls about its axis ofrotation DD, and is pivotally moveable within established limitationsabout the pin 266 along the BB axis and the pin 268 along the CC axis,for automatic alignment and engagement with the wire on the capstan.

[0036] As shown in FIG. 5B, the width of the roller 222, along itslongitudinal axis DD, is sized at close to the inside width of thecapstan 20 for engaging either all of the wraps 11C of wire on thecapstan, or for engaging all but one or two wraps of wire, and formaintaining even pressure on such wraps of wire. In the latter instance,provision is made for adjusting the position of the roller assembly forindexing of the roller on the wraps of wire; such as is sometimes usefulwhen running wire of substantially different sized on the same machine,and in instances when the wire tend to not index on the capstan.Provision for indexing or adjusting of the position of the roller alongthe AA axis with respect to the sides of the capstan can be accomplishedwith any suitable arrangement such as simply with slots through whichfasteners 226 extend, or repositioning of the support block on the shaft234.

[0037] Advantageously, maintaining an even pressure on all wraps of thewire, as opposed to maintaining pressure of the last wrap asconventional prior wire containment apparatus, permits the use of lesspressure for maintaining the wire sufficiently snugly against thecapstan for drawing the wire through the die. In other words, the wireis maintained snugly against the capstan for a substantially greaterdistance (measuring the wrapping length of the wire around the capstan)as compared with prior wire containment apparatus. As a result, the wirecontainment apparatus 200 results in greater traction developed betweenthe capstan and the wire.

[0038] In further keeping with the invention, the wire containmentapparatus of the present invention is preferably located in the quadrantproximate the exit point of the wire from the capstan. To this end, inthe embodiment shown, the wire containment apparatus is located in thelower quadrant opposite the speed compensating arm. As a result, thewire is held firmly against the capstan until just prior to unwrappingfrom the capstan.

[0039] Those skilled in the art will appreciate alternate embodimentsthat fall within wire containment systems of the present invention. Byway of example only, it will be understood that the actuator may be ofany suitable type operatively connected to the roller assembly with asuitably designed linkage assembly for controlling position of theroller assembly with regard to the capstan as described. By way ofexample only, a double-acting actuator responsive to pressure appliedfrom both sides of the piston, a piston-seal actuator (as opposed to adiaphragm-type actuator), a hydraulic actuator, a mechanical orelectromechanical actuator provided with electric motor, and other typesof actuators and associated linkage assemblies may be substituted andused with in the scope of the invention.

[0040] Wire containment system of the present invention may be used onother conventional and non-conventional wire drawing machines having acapstan, and in which there is a need to hold the wire against thecapstan to develop the necessary traction for drawing the wire throughone or more draw dies.

[0041] With the foregoing wire containment system, less pressure isapplied to each wrap of wire, while developing the same or greatertraction of conventional prior roller arrangements that engage the lastwrap of wire. Positioning the roller proximate the speed compensator armreduces the “free drop” of the wire as it exits the capstan, allowingthe capstan to be positioned closer to the floor, and reduces the dragon the speed compensating arm since it does not need to carry as muchwire weight or hold the wire off the floor, permitting to operate withless air pressure and at greater sensitivity. Such reduced wire dropalso allows for lower wire entry and exit on the machine, reducing theoverall height of the machine. Wire of substantially different sized canbe run on the machine without having to change the roller. And theroller hereof eliminates the task of aligning the prior roller with thelast wire wrap prior to engaging the pressure roller, by virtue of beingadapted for pivoting about orthogonal axes as it is brought intoengagement with the wire on the capstan resulting in automatic alignmentof the roller 222 along the entire width of the capstan.

We claim:
 1. A wire drawing machine comprising: a draw die; a capstanmounted for rotation about a horizontal axis and positioned for drawingwire through the draw die, the capstan having an upper wire-entry sideand a lower wire-exit side; and a roller connected for pivoting about ahorizontal axis parallel to the axis of the capstan and about a secondaxis orthogonal thereto for engaging wire on the lower exit side of thecapstan, the roller being sized to substantially overlap the width ofthe capstan and engage the wire wrapped thereon.